Noise gate pedal questions :)

Just a few questions about noise gate pedals, because I have quite a few pedals and could do without some of the extra noise:

1. Is there a big difference between the Boss NS-2 and the ISP Decimator?

2. Will either of those pedals get rid of the weird noises that accompany the switches on some of my pedals? (when I turn them on or off)

3. If I want to reduce amp hum AND single coil pickup/effect pedal noise, do I need separate noise gate pedals for the front of the amp and its effects loop? (I don't use the effects loop with my other pedals because I don't use the amp's distortion)

None of my pedals are that noisy (but they could be cleaned up), it's mostly my single coil pickups and white noise from the amp, plus the pedal switches.

The ISP range won't suck tone like the NS-2 or mxr smart gate. The normal iSP decimator will clean up pedals and guitar noise in your signal path, while its more expensive brother the G-String will do that plus cancel amp hum